Family of Zelda Townsend arrive to the barber and beauty salon Danny's Devine Design after Zelda Townsend was fatally shot and her husband Danny Townsend injured during an attempted car burglary by a 17-year-old Wednesday night, on S. Broad Ave. near Cleveland Ave. in New Orleans, Thursday, May 9, 2019.

Another young suspect was arrested Tuesday in the fatal shooting of a security guard who interrupted an auto burglary that has re-ignited a debate on juvenile crime, New Orleans police said.

Police said further investigation led them to the third suspect in the killing of Zelda Townsend, who was shot to death in the 2700 block of Cleveland Avenue late on May 8. Her husband was also wounded in what police described as an exchange of gunfire.

Investigators last week arrested the alleged shooter, 17-year-old Emanuel Pipkins, and his 18-year-old girlfriend, Byrielle Hebert.

Police said the third suspect was booked on counts of second-degree murder, burglary, and conspiracy to commit burglary.

Officials did not name the newly arrested suspect. Further details on the third suspect's age and identity could come when and if the suspect is transferred to adult court.

In Louisiana, teens over 15 accused of murder are automatically transferred to adult court. 14-year-olds can be transferred at the discretion of a judge.

Investigators believe a car alarm alerted Zelda Townsend and her husband, Danny, to a car break-in. They went outside and tried to hold the boy they found inside the car, but he shot both of them and escaped.

Pipkins was left wounded in an exchange of gunfire, however. He faces second-degree murder and other counts. Hebert was booked on manslaughter and other counts.

Although homicides are at historic lows in New Orleans, police say they have seen a near doubling in auto burglaries this year. Many are tied to youths, investigators believe.

District Attorney Leon Cannizzaro says he sees juvenile crime as the biggest crime problem facing the city, and New Orleans Mayor LaToya Cantrell has vowed to take a “holistic” approach to reining in youth crime.

Follow Matt Sledge on Twitter, @mgsledge.